determine the number of moles in 4.21 x 10^23 molecules of cacl2

The number of moles in 4.21 x 10²³ molecules of CaCl2 is 0.69moles.

HOW TO CALCULATE NUMBER OF MOLES:

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0.699 mole CaCl₂

To get the number of moles we use the Avogadro's number.

Avogadro's number is 6.022 x 10^23.

But, 1 mole of a compound contains  6.022 x 10^23 molecules

In this case;

we are given 4.21 × 10^23 molecules of CaCl₂

Therefore, to get the number of moles

Moles = Number of molecules ÷ Avogadro's constant

          = 4.21 × 10^23 molecules ÷  6.022 x 10^23 molecules/mole

          = 0.699 mole CaCl₂

Hence, the number of moles is 0.699 mole of CaCl₂

a). in this case, dh> 0 and sd> 0. if t becomes larger, the term "-tds" will become more negative. at some point, it is possible that -dts will be more negative than the dh is positive, and the reaction will become spontaneous. this is probably the correct answer, but you should look at all of the other possibilities and make sure of that.